Various 2-[(substituted heterocyclic)alkyl]-1H-benz[de]isoquinoline-1,3(2H)-diones having central nervous system and anti-inflammatory activity are disclosed by Wade et al. in U.S. Pat. Nos. 3,935,227; 3,940,397; 3,940,398; 3,947,452; and 3,959,286. Also, Schenker et al. in U.S. Pat. No. 3,247,208 disclose that 1H-benz[de]isoquinoline-1,3(2H)-diones having a (1-substituted-4-piperidinyl group in the 2-position possess anesthetic properties.